如果x+y=5,xy=0,则x²y+xy²=?x²-xy+y²=?_数学解答

如果x+y=5,xy=0,则x²y+xy²=?x²-xy+y²=?

人气：195 ℃　时间：2020-01-20 04:45:39

解答

x+y=5,xy=0,则
x²y+xy²
=xy ( x+y)
= 0 x 5
= 0
x²-xy+y²
= x²+2xy+y² -3xy
=(x+y ) ² -3xy
=5x5 - 0
= 25